2. Background
2.3 Materials characterization and analytical techniques
2.3.3 X-ray diffraction (XRD)
Solid matter can be described as being either amorphous, atoms arranged in a random way similar to the disorder found in liquids, or crystalline, atoms arranged in a regular pattern where a volume element (smallest in a material) that by repetition in three dimensions describes the crystal. This smallest volume element is called a unit cell, the dimensions of which are described by three axes: a, b, c and the angles between them alpha, beta, gamma (Figure 2.20) [90].
Figure 2.20: A unit cell with x, y, and z coordinate axes showing axial lengths (a, b, and c) and interaxiDODQJOHVĮȕDQGȖ>@
An electron in an alternating electromagnetic field will oscillate with the same frequency as the field. When an X-ray beam hits an atom, the electrons around the atom start to oscillate with the same frequency as the incoming beam. For amorphous materials, there will be destruc- tive interference in all directions, that is, the combining waves are out of phase and there is no resultant energy leaving the solid sample. However the atoms in a crystal are arranged in a regular pattern, and therefore yield constructive interference in some directions (Figure 2.21) [90].
Figure 2.21: (a) Demonstration of how two waves (labled 1 and 2) that have the same wave- length ȜDQGUHPDLQLQSKDVHDIWHUDVFDWWHULQJHYHQWZDYHV¶DQG¶FRQVWUXFWLYHO\LQWHUIHUH
with one another. The amplitudes of the scattered wave add together in a resultant wave. (b) Demonstration of how two waves (labeled 3 and 4) that have the same wavelength and become
out of phase after a scattering event (waves 3’ and 4’) destructively interfere with one another. The amplitudes of the two scattered waves cancel one another [90].
The waves will be in phase and there will be well defined X-ray beams leaving the sample. Hence, a diffracted beam may be described as a beam composed of a large number of scattered rays mutually reinforcing one another.
X-ray reflections originate from series of parallel planes inside the crystal: the orientation and interplanar spacing’s of these planes are defined by the three integers h, k, l called Miller indices. A given set of planes with indices h, k, l cut the a-axis of the unit cell in h sections, the b axis in k sections and the c axis in l sections (Figure 2.23). A zero indicates that the planes are parallel to the corresponding axis. E.g. the (2,2,0) planes cut the a– and the b– axes in half, but are parallel to the c– axis.
Figure 2.22: Example planes sections for respective h, k, l indices.
As mentioned, the indices values are used to calculate interplanar spacing dhkl, which for a
crystal structure of cubic symmetry for example, can be calculated according to Eq. (2.30).
in which a is the lattice parameter (unit cell edge length). The interatomic spacing, in conjunction with the angle of the diffracted beam and the incident wavelength upon the planes are related through Braggs law, Eq. (2.31).
Eq. (2.31)
where n is WKHRUGHURIUHIOHFWLRQZKLFKPD\EHDQLQWHJHU«FRQVLVWHQWZLWKVLQșQRW exceeding unity.
Powder XRD is one of the most widely used x-ray diffraction techniques for characteriz- ing materials. While samples are generally analyzed in powder form, consisting of fine grains of single crystalline materials, the technique is also used widely for studying particles in liquid suspensions or polycrystalline solids (bulk or thin film materials). As powder, the crystalline domains are randomly oriented in the sample, therefore when the 2-D diffraction pattern is recorded it shows concentric rings of scattering peaks corresponding to the various interatomic spacing’s in the crystal lattice. The positions and the intensities of the peaks are used for identi- fying the underlying structure (or phase) of the material. For example, the diffraction lines of graphite are different from diamond even though they both are made of carbon atoms. This phase identification is important because the material properties are highly dependent on structure. Likewise, the diffraction patterns for doped xerogels show a transition from amorphous to crystalline with heat treatment.
Figure 2.23: Xray diffraction of xerogels doped with 0.3% mol of europium and heat-treated at different temperatures displaying the transition from amorphous to crystalline material [91].
2.3.4 Raman Spectroscopy
Like XRD, Raman spectroscopy provides information on chemical structures and physi- cal forms to identify substances from the characteristic spectral patterns (“fingerprinting”). When light interacts with matter, the photons which make up the light may be absorbed or scattered, or pass straight through it without interacting. If the energy of an incident photon corresponds to the energy gap between the ground state of a molecule and an excited state, the photon may be absorbed and the molecule promoted to the higher energy excited state. It is this change which is measured in absorption spectroscopy by the detection of the loss of that energy of radiation from the light. However, it is also possible for the photon to interact with the molecule and scatter from it, in which case there is no need for the photon to have an energy matching the difference between two energy levels of the molecule. The scattered photons can be observed by collecting light at an angle to the incident light beam, and provided there is no absorption from any elec-
tronic transitions which have similar energies to that of the incident light, the efficiency increases as the fourth power of the frequency of the incident light [92].
Radiation is often characterized by its wavelength (ȜKRZHYHULQVSHFWURVFRS\WKHLQWe- raction of radiation with states of the molecule being examined are discussed in terms of energy, therefore frequenF\ȞRUZDYHQXPEHUȦDUHJHQHUDOO\XVHGDVWKH\DUHOLQHDUO\UHODWHGZLWK energy (E). The relationships between these scale are given in Eq. (2.32), Eq. (2.33), and Eq. (2.34).
Ȝ FȞ Eq. (2.32)
Ȟ ¨(K Eq. (2.33)
Ȧ ȞF Ȝ Eq. (2.34)
Energy is therefore proportional to the reciprocal of wavelength allowing characteristic intense scattering frequencies to be used as fingerprint values to determine or confirm the presence of various materials. An example of a Raman scattering for different carbon hydrides can be observed in Figure 2.24.
Figure 2.24: Raman scattering “fingerprints” for both acetone and ethanol.
2.3.5 Electrochemical measurement
Electrochemical measurements can be taken as “continuous” or “intermittent” by control- ling either the current or voltage, or both. Information can be collected by electrochemical measurement regarding chemical reactions taking place within battery electrodes and kinetic properties of battery components, which aid in explaining practical reaction voltages and charac- teristic discharge-charge behavior and deviation from theoretical performance. Typical testing procedures involve constant-current (CC) cycling or constant-current-constant-voltage (CCCV) cycling in order to understand electrochemical properties of cycling batteries. CC cycling requires that current remain constant for the duration of discharging and charging, but does not require that both the currents be equal. Likewise for CCCV cycling, but a voltage hold takes place at the upper cut-off voltage for a pre-set time interval or low current cut-off. Utilization of a voltage hold allows for equilibration of mobile species into an electrode.
One method of presenting and analyzing information is through use of discharge and charge curves, in which the cell voltage is plotted as a function of the state of charge. The
relationships for a single material can vary significantly depending upon the rate at which the energy is extracted from, or added to the cell. Likewise, curves vary extensively for different materials. Figure 2.25 shows an example of a discharge curve for various types of materials.
Figure 2.25: Schematic representation of three different types of discharge curves: one that is flat, one that has more than one flat curve, and a slanted/stretched S-shaped curve with a relative-
ly large slope [5].
The flat plateaus represent multiphase reactions with potentials that are essentially independent of the state of charge of the cell. A sloping plateau allows for potential misinterpretation as it could be the result of undesirable reactions between two or more components of the battery, such as the electrolyte and active material.
The information obtained from electrochemical measurements is not only limited to observation of reaction voltages, but is useful for observation of polarization losses (Chapter 4),
of materials (Chapter 6). Electrochemical measurements are also used to show cycle life through repeated cycling, and in the case of degradation, explain the mechanisms for reduced capacity (Chapter 4).
References
1. Tarascon, J.; Armand, M., Issues and challenges facing rechargeable lithium batteries.
Nature, 414 (2001) 359-367.
2. Scrosati, B. Battery technology - Challenge of portable power. Nature, 375 (1995) 557-
558.
3. Van den Bossche, P.; Vergels, F.; Van Mierlo, J.; Matheys, J.; Van Autenboer, W.;
SUBAT: An assessment of sustainable battery technology. Journal of Power Sources, 162 (2006) 913-916.
4. Linden, D. and Reddy, T. B, Handbook of Batteries, 3rd Edition, 2002, McGraw-Hill,
New York.
5. Huggins, R.A., Handbook of Batteries: Materials Science Aspects, Springer, 2008.
6. Aydinol, M.; Ceder, G., First-principles prediction of insertion potentials in Li-Mn oxides
for secondary Li batteries. Journal of the Electrochemical Society, 144 (1997) 3832-3835.
7. Manthiram, A., Materials Aspects: an overview in Lithium batteries : science and
technology, Nazri G.: Pistoia G. (Ed.) Kluwer Academic Publishers, 2004.
8. Brockris, J. O’M. and Reddy, A.K.N., Modern Electrochemistry, Vol. 2, Plenum, New
York, 1970, p. 644.
9. Pletcher, D., A First Course in Electrode Processes, The Electrochemistry Consultancy,
Alresford, Hants, 1991.
10. Manthiram, A.; Kim, J., Low temperature synthesis of insertion oxides for lithium
batteries. Chemistry of Materials, 10 (1998) 2895-2909.
11. Owen, J. R., Rechargeable lithium batteries. Chemical Society Reviews, 26 (1997) 259-
267.
12. Winter, M.; Besenhard, J.; Spahr, M.; Novak, P., Insertion electrode materials for
rechargeable lithium batteries. Advanced Materials, 10 (1998) 725-763.
13. Xing, W.; Xue, J.; Zheng, T.; Gibaud, A.; Dahn, J., Correlation between lithium
intercalation capacity and microstructure in hard carbons. Journal of the Electrochemical Society 143, (1996) 3482-3491.
15. Buiel, E.; Dahn, J., Reduction of the irreversible capacity in hard-carbon anode materials prepared from sucrose for Li-ion batteries. Journal of the Electrochemical Society, 145 (1998) 1977-1981.
16. Dahn, J.; Sleigh, A.; Shi, H.; Reimers, J.; Zhong, Q.; Way, B., Dependence of the
electrochemical intercalation of lithium in carbons on the crystal-structure of the carbon. Electrochimica Acta, 38 (1993) 1179-1191.
17. Zheng, T.; Reimers, J.; Dahn, J., effect of turbostratic disorder in graphitic carbon hosts
on the intercalation of lithium. Physical Review B, 51 (1995), 734-741.
18. Zheng, T.; Dahn, J., The effect of turbostratic disorder on the staging transitions in
lithium intercalated graphite. Synthetic Metals, 73 (1995) 1-7.
19. Zheng, T.; Dahn, J., Effect of turbostratic disorder on the staging phase diagram of
lithium-intercalated graphitic carbon hosts. Physical Review B, 1996 3061-3071.
20. Che, G. L.; Lakshmi, B. B.; Fisher, E. R.; Martin, C. R., Carbon nanotubule membranes
for electrochemical energy storage and production. Nature, 393 (1998) 346-349.
21. Gao, B.; Kleinhammes, A.; Tang, X. P.; Bower, C.; Fleming, L.; Wu, Y.; Zhou, O.,
Electrochemical intercalation of single-walled carbon nanotubes with lithium. Chemical Physics Letters, 307 (1999) 153-157.
22. Leroux, F.; Metenier, K.; Gautier, S.; Frackowiak, E.; Bonnamy, S.; Beguin, F.,
Electrochemical insertion of lithium in catalytic multi-walled carbon nanotubes. Journal of Power Sources, 81 (1999) 317-322.
23. Claye, A.; Fischer, J.; Huffman, C.; Rinzler, A.; Smalley, R., Solid-state electrochemistry
of the Li single wall carbon nanotube system. Journal of the Electrochemical Society, 147 (2000) 2845-2852.
24. Endo, M.; Kim, C.; Nishimura, K.; Fujino, T.; Miyashita, K., Recent development of
carbon materials for Li ion batteries. Carbon, 38 (2000) 183-197.
25. Lu, W.; Chung, D., Anodic performance of vapor-derived carbon filaments in lithium-ion
secondary battery. Carbon, 39 (2001) 493-496.
26. Frackowiak, E.; Beguin, F., Electrochemical storage of energy in carbon nanotubes and
nanostructured carbons. Carbon, 40 (2002) 1775-1787.
27. Ng, S.; Wang, J.; Guo, Z.; Wang, G.; Liu, H., Single wall carbon nanotube paper as
28. Shimoda, H.; Gao, B.; Tang, X.; Kleinhammes, A.; Fleming, L.; Wu, Y.; Zhou, O., Lithium intercalation into opened single-wall carbon nanotubes: Storage capacity and electronic properties. Physical Review Letters, 88 (2002) 011502.
29. Wu, Y. P.; Rahm, E.; Holze, R., Carbon anode materials for lithium ion batteries. Journal
of Power Sources, 114 (2003) 228-236.
30. Yoon, S.; Park, C.; Yang, H.; Korai, Y.; Mochida, I.; Baker, R.; and Rodriguez, N. A
Conceptual Model for the Structure of Catalytically Grown Carbon Nano-Fibers. Carbon, 42 (2003) 21-32.
31. Menier, V.; Kephart, J.; Roland, C.; Bernholc, J., Ab initio investigations of lithium
diffusion in carbon nanotube systems. Physical Review Letters, 88 (2002) 075506.
32. Yang, Z. H.; Wu, H. Q.; Simard, B., Charge-discharge characteristics of raw acid-
oxidized carbon nanotubes. Electrochemistry Communications, 4 (2002) 574-578.
33. Nazar L. F.; Crosnier, O., Anode and compoisite anodes: an overview in Lithium
batteries : science and technology, Nazri G.: Pisotoia G. (Ed.) Kluwer Academic Publishers, 2004
34. Kasavajjula, U.; Wang, C.; Appleby, A., Nano- and bulk-silicon-based insertion anodes
for lithium-ion secondary cells. Journal of Power Sources, 163 (2007) 1003.
35. Chan, C.; Ruffo, R.; Hong, S.; Huggins, R.; Cui, Y. J. Power Sources, 189 (2009) 34.
36. Liu, Y.; Wen, Z.; Wang, X.; Yang, X.; Hirano, A.; Imanishi, N.; Takeda, Y.,
Improvement of cycling stability of Si anode by mechanochemcial reduction and carbon coating. Journal of Power Sources, 189 (2009) 480.
37. Obrovac, M.; Christensen, L.; Le, D.; Dahnb, J., Alloy design for lithium-ion battery
anodes. Journal of the Electrochemical Society, 154 (2007) 849.
38. Wu, X.; Wang, Z.; Chen, L.; Huang, X., Ag-enhanced SEI formation on Si particles for
lithium batteries. Electrochemistry Communications, 5 (2003) 935.
39. Chan, C.; Peng, H.; Liu, G.; McIlwrath, K.; Zhang, X.; Huggins, R.; Cui, Y., High-
performance lithium battery anodes using silicon nanowires. Nature Nanotechnology, 13 (2008) 31.
40. Patil Patil, A.; Patil, V.; Shin, D.; Choi, J.; Paik, D.; Yoon, S., Issue and challenges facing rechargeable thin film lithium batteries. Materials Research Bulletin, 43 (2008) 1913.
41. Zhang, X.; Pan, G.; Li, G.; Qu, J.; Gao, X., Si-Si3N4 composites as anode materials for
lithium ion batteries. Solid State Ionics, 178 (2007) 1107.
42. Zhang, X.; Huang, P.; Li, G.; Yan, T.; Pan, G.; Gao, X., Si-AB(5) composites as anode
43. Jiang, T.; Zhang, S.; Qiu, X.; Zhu, W.; Chen, L., Preparation and characterization of silicon-based three-dimensional cellular anode for lithium ion battery. Electrochemistry Communications, 9 (2007) 930.
44. Wang, X.; Wen, Z.; Liu, Y.; Wu, X., A novel composite containing nanosized silicon and
tin as anode material for lithium ion batteries. Electrochimica Acta, 54 (2009) 4662.
45. Zuo, P.; Yin, G.; Yang, Z.; Wang, Z.; Cheng, X.; Jia, D.; Du, C., Improvement of cycle
performance for silicon/carbon composite used as anode for lithium ion batteries. Materials Chemistry and Physics, 115 (2009) 757.
46. Li, J.; Christensen, L.; Obrovac, M.; Hewitt, K.; Dahn, J., Effect of heat treatment on Si
electrodes using polyvinylidene fluoride binder. Journal of the Electrochemical Society, 155 (2008) 234.
47. Key, B.; Bhattacharyya, R.; Morcrette, M.; Seznec, V.; Tarascon, J.; Grey, C., Real-Time
NMR Investigations of Structural Changes in Silicon Electrodes for Lithium-Ion Batteries. Journal of the American Chemical Society, 131 (2009) 9239.
48. Kang, Y.; Lee, S.; Kim, S.; Jeong, G.; Sung, M.; Choi, W.; Kim, S., Phase transitions
explanatory of the electrochemical degradation mechanism of Si based materials. Electrochemistry Communications, 9 (2007) 959.
49. Yoshio, M.; Kugino, S.; Dimov, N., Electrochemical behaviors of silicon based anode
material. Journal of Power Sources, 153 (2006) 375.
50. Luo, Z.; Fan, D.; Liu, X.; Mao, H.; Yao, C.; Deng, Z., High performance silicon carbon
composite anode materials for lithium ion batteries. Journal of Power Sources, 189 (2009) 16.
51. Ding, N.; Xu, J.; Yao, Y.; Wegner, G.; Lieberwirth, I.; Chen, C., Improvement of
cyclability of Si as anode for Li-ion batteries. Journal of Power Sources, 192 (2009) 644.
52. Liu, Y.; Wen, Z.; Wang, X.; Yang, X.; Hirano, A.; Imanishi, N.; Takeda, Y.,
Improvement of cycling stability of Si anode by mechanochemcial reduction and carbon coating. Journal of Power Sources, 189 (2009) 480.
53. Bruce, P., Energy storage beyond the horizon: Rechargeable lithium batteries. Solid State
Ionics, 179 (2008) 752.
54. Limthongkul, P.; Jang, Y.; Dudney, N.; Chiang, Y., Electrochemically-driven solid-state
amorphization in lithium-silicon alloys and implications for lithium storage. Acta Materialia, 51 (2003) 1103.
55. Yang, X.; Wen, Z.; Zhang, L.; You, M., Synthesis and electrochemical properties of
novel silicon-based composite anode for lithium-ion batteries. Journal of Alloys and Compounds, 464 (2008) 265.
56. Peng, K.; Jie, J.; Zhang, W.; Lee, S., Silicon nanowires for rechargeable lithium-ion
57. Beattie, S.; Larcher, D.; Morcrette, M.; Simon, B.; Tarascon, J., Si electrodes for li-ion batteries - A new way to look at an old problem. Journal of the Electrochemical Society, 115 (2008) 158.
58. Shodai, T.; Okada, S.; Tobishima, S.; Yamaki, J., Study of Li(3-x)M(x)N (M:Co,Ni or
Cu) system for use as anode material in lithium rechargeable cells. Solid State Ionics, 86 (1996) 785-789.
59. Idota, Y.; Kubota, T.; Matsufuji, A.; Maekawa, Y.; Miyasaka, T., Tin-based amorphous
oxide: A high-capacity lithium-ion-storage material. Science, 276 (1997) 1395-1397.
60. Kepler, K.; Vaughey, J.; Thackeray, M., LixCu6Sn5 (0 < x < 13): An intermetallic
insertion electrode for rechargeable lithium batteries. Electrochemical and Solid State Letters, 2 (1999) 307-309.
61. Courtney, I.; McKinnon, W.; Dahn, J., On the aggregation of tin in SnO composite
glasses caused by the reversible reaction with lithium. Journal of the Electrochemical Society, 146 (1999) 59-68.
62. Denis, S.; Baudrin, E.; Touboul, M.; Tarascon, J. M., Synthesis and electrochemical
properties of amorphous vanadates of general formula RVO4 (R = In, Cr, Fe, Al, Y) vs. Li. Journal of the Electrochemical Society, 144 (1997) 4099-4109.
63. Poizot, P.; Laruelle, S.; Grugeon, S.; Dupont, L.; Tarascon, J., Nano-sized transition-
metaloxides as negative-electrode materials for lithium-ion batteries. Nature, 407 (2000) 496-499.
64. Mizushima, K.; Jones, P.; Wiseman, P.; Goodenough, J., lixcoo2 "(oless-thanxless-than-
or-equal-to1) - a new cathode material for batteries of high-energy density. Materials Research Bulletin, 15 (1980) 783-789.
65. Whittingham, M., Lithium batteries and cathode materials. Chemical Reviews, 104
(2004) 4271-4301.
66. Reimers, J.; Dahn, J., electrochemical and insitu x-ray-diffraction studies of lithium
intercalation in lixcoo2. Journal of the Electrochemical Society, 139 (1992) 2091-2097.
67. Ohzuku, T.; Ueda, A., solid-state redox reactions of licoo2 (r(3)over-bar-m) for 4 volt
secondary lithium cells. Journal of the Electrochemical Society, 141 (1994) 2972-2977.
68. Johnston, W.; Heikes, R.; Sestrich, D., the preparation, crystallography, and magnetic
properties of the lixco(1-x)o system. Journal of Physics and Chemistry of Solids, 7 (1958) 1-13.
69. Hoshino, K.; Murakami, T.; Atsuka, A.; Ozaki, Y.; Watanabe, S.; and Takahashi, Y. Nature Technology Rep., 40 (1994) 31-35.
70. Ohzuku, T.; Kitagawa, M.; Hirai, T., electrochemistry of manganese-dioxide in lithium
nonaqueous cell .3. X-ray diffractional study on the reduction of spinel-related manganese-dioxide. Journal of the Electrochemical Society, 137 (1990) 769-775.
71. Mukerjee, S.; Thurston, T.; Jisrawi, N.; Yang, X.; McBreen, J.; Daroux, M.; Xing, X.,
Structural evolution of LixMn2O4 in lithium-ion battery cells measured in situ using synchrotron X-ray diffraction techniques. Journal of the Electrochemical Society, 145 (1998) 466-472.
72. Thackeray, M.; Mansuetto, M.; Bates, J., Structural stability of LiMn2O4 electrodes for
lithium batteries. Journal of Power Sources, 68 (1997) 153-158.
73. Shin, Y.; Manthiram, A., Microstrain and capacity fade in spinel manganese oxides.
Electrochemical and Solid State Letters, 5 (2002), A55-A58.
74. Thackeray, M., structural considerations of layered and spinel lithiated oxides for lithium
ion batteries. Journal of the Electrochemical Society, 142 (1995) 2558-2563.
75. Cho, J.; Kim, G.; Lim, H.; Kim, C.; Yoo, S., Improvement of structural stability of
LiMn2O4 cathode material on 55 degrees C cycling by sol-gel coating of LiCoO2. Electrochemical and Solid State Letters, 2 (1999) 607-609.
76. Park, S.; Han, Y.; Kang, Y.; Lee, P.; Ahn, S.; Lee, H.; Lee, J., Electrochemical properties
of LiCoO2-coated LiMn2O4 prepared by solution-based chemical process. Journal of the Electrochemical Society, 148 (2001) A680-A686.
77. Kannan, A.; Manthiram, A., Surface/Chemically modified LiMn2O4 cathodes for
lithium-ion batteries. Electrochemical and Solid State Letters, 5 (2002) A167-A169.
78. Megahed, S.; Scrosati, B., Lithium-ion rechargeable batteries. Journal of Power Sources,
51 (1994) 79-104.
79. Chung, S.; Bloking, J.; Chiang, Y., Electronically conductive phospho-olivines as lithium
storage electrodes. Nature Materials, 1 (2002) 123-128.
80. Goodenough, J. B., Nanjundaswamy, K. S., and Masquelier, C. (1997), International
Patent Application, WO 97/40541.
81. Ravet, N.; Goodenough, J B.; Besner, S.; Simoneau, M.; Hovington, P.; Armand, M.
82. Ravet, N.; Besner, S.; Simoneau, M.; Vallée, A.; Armand M.; Magnan J.-F. (Hydro- Quebec) European Patent 1049182A2, 2000.
83. Ritchie, A.; Bowles, G.; Scattergood, D., Lithium-ion/iron sulphide rechargeable
batteries. Journal of Power Sources, 136 (2004) 276-280.
84. Whittingham, M.; Chemistry of intercalation compounds - Metal guests in chalcogenide
hosts. Progress in solid state chemistry, 12 (1978) 41-99.
85. Winter, R.; Heitjans, P., Li+ diffusion and its structural basis in the nanocrystalline and
amorphous forms of two-dimensionally ion-conducting LixTiS2. Journal of Physical Chemistry B, 105 (2001) 6108.
86. Tarascon, J.; Armand, M., Issues and challenges facing rechargeable lithium batteries.
Nature, 414 (2001) 359.
87. Randles, J., Kinetics of rapid electrode reactions. Discussions of the Faraday Society, 1
(1947) 11-19.
88. Warburg, E., Polarization capacity of platinum. Annalen Der Physik, 6 (1901) 125-135.
89. Ho, C.; Raistrick, I.D.; Huggins, R.A., Application of AC Techniques to teh Study of
Lithium Diffusion in Tungsten Trioxide Thin-Films. Journal of The Electrochemical Society, 127 (1980) 343-350.
90. Callister, W.D., Materials Science and Engineering an Introduction 7th ed. John Wiley &
Sons Inc., 2007.
91. L.A. Rocha, L.R. Avila, B.L. Caetano, E.F. Molina, H.C. Sacco, K.J. Ciuffi, P.S. Calefi,
E.J. Nassar, “Europium incorporated into titanium oxide by the sol-gel method”. Mate- rials Research, 8 (2005) 82.
92. Smith, E. And Dent, G. Modern Raman Spectroscopy – A Practical Approach. John
3.
Solid Electrolyte
3.1 Introduction
Recent popularization of various kinds of portable electronic devices has driven the im- portance of energy devices like secondary batteries, fuel cells, and capacitors to new heights. It is widely understood that all-solid-state energy storage is most promising for improving safety and reliability of these devices [1]. As a key material of all-solid-state energy devices, solid electro- lytes have been extensively studied in the fields of materials science and electrochemistry. Many research efforts have focused on preparation of solid electrolytes with a broad spectrum of materials and manufacturing methods.
For any rechargeable lithium battery, the electrolyte material must permit the repeated
and rapid transfer of Li+between the anode and cathode over a predetermined set of operating
conditions (voltage, temperature, and current), without significant deterioration. Ideally, an electrolyte material would be electronically insulating, ultra-thin, lightweight, free of hazards and inexpensive. Inorganic solid electrolytes offer both advantages and disadvantages over liquid and
organic polymer electrolytes. For the required rapid transport of Li+ across the electrolyte, the
product of the resistivity and electrolyte thickness must be minimized (Ahrenius Equation,